顺丁橡胶和白炭黑对炭黑/天然橡胶复合材料性能的影响

试验研究顺丁橡胶(BR)和白炭黑对炭黑/天然橡胶(NR)复合材料性能的影响。结果表明:与炭黑/NR复合材料相比,炭黑/NR/BR胶料的焦烧时间略有缩短,交联程度增大,硫化胶的300%定伸应力增大,压缩生热降低,抗切割性能下降,耐磨性能提高,滚动阻力减小;炭黑/白炭黑/NR胶料的交联程度减小,硫化胶的拉断伸长率和撕裂强度明显增大,压缩生热略有升高,抗切割性能和耐磨性能提高,滚动阻力增大(须通过加入偶联剂予以改善)。     

高硬度丁腈橡胶材料的研制

通过丁腈橡胶与大用量炭黑(喷雾炭黑和炭黑N330)共混,或与三元尼龙(尼龙6+尼龙66+尼龙610共聚物)、酚醛树脂和不饱和羧酸盐等分别共混,制备了高硬度丁腈橡胶材料。结果表明,喷雾炭黑相同用量时,采用复合硫化体系的硫化胶具有最佳综合性能,采用过氧化物硫化体系的硫化胶具有最好弹性;丁腈橡胶/三元尼龙复合材料的焦烧时间最短,硫化速度最快,综合性能最好;随着酚醛树脂用量的增大,胶料的硬度、压缩模量和撕裂强度增大,拉伸强度先增大并在用量为30份时快速下降,拉断伸长率随之下降,冲击弹性变差,耐油性有适当程度地提高;在齐聚酯、甲基丙烯酸镁、甲基丙烯酸锌(SR634)和丙烯酸锌(SR633)分别与丁腈橡胶制成的纳米复合材料中,甲基丙烯酸镁/丁腈橡胶纳米复合材料的综合性能最好。     

银菊胶在汽车橡胶制品中的应用

为了探究银菊胶可替代天然橡胶的程度,进行了含各种用量的银菊胶胶料的试验。结果表明,在天然橡胶胶料中,当银菊胶用量为40份时,胶料的焦烧时间和硫化时间与纯天然橡胶胶料相比几乎没有发生变化;其硫化胶的定伸应力和撕裂强度也基本相同。最后在胶料中采用10份蛋壳替代10份炭黑,其胶料的硫变曲线和硫化胶的力学性能也基本相当。     

碱式碳酸镁阻燃天然橡胶复合材料的 制备与性能研究

在天然橡胶（NR）中添加碱式碳酸镁以制备阻燃橡胶复合材料,研究碱式碳酸镁对NR复合材料性能的影响。结果表明：随着碱式碳酸镁用量的增大,NR胶料的硫化转矩增大,焦烧时间缩短,硫化胶的300%定伸应力和撕裂强度先增大后减小,氧指数逐渐增大,阻燃性能提高;碱式碳酸镁的分解温度范围较宽,其填充NR硫化胶的残炭较密集,且均匀地覆盖在硫化胶表面。     

弓弦大麻纤维补强填料在天然橡胶中的应用研究

研究了填充弓弦大麻纤维（BHF）填料和炭黑的天然橡胶（NR）胶料的硫化特性和物理性能。结果表明,随着填料用量增大,硫化胶的焦烧时间和硫化时间缩短,而最大转矩增大;硫化胶的拉断伸长率和回弹值降低,而硬度、定伸应力、耐磨性能及密度提高。当填料用量为40份时,两种硫化胶的拉伸强度达到最大值。填充炭黑的NR硫化胶的拉伸强度约为填充BHF填料硫化胶的1.5倍,这可能是由BHF填料较高的水分含量和较大的粒径所致,但是填充BHF填料的NR硫化胶具有更高的硬度。     

不同硫化体系对天然橡胶的动静态性能的影响研究

分别制备了以炭黑和白炭黑为补强填料的不同硫化体系天然橡胶(NR)复合材料,研究硫化体系对NR胶料静态和动态性能的影响。结果表明:普通硫化体系硫化胶具有较高的交联密度、较好的物理性能和优异的耐磨性能;对于白炭黑补强体系,普通硫化体系硫化胶具有最低的滚动阻力;而对于炭黑补强体系,平衡硫化体系硫化胶具有最低的滚动阻力;胶料拉伸强度的增大有利于耐磨性的提高。     

稻壳源白炭黑/炭黑/天然橡胶复合材料的性能研究

试验研究稻壳源白炭黑/炭黑并用对天然橡胶硫化胶性能的影响。结果表明:当稻壳源白炭黑/炭黑用量比较高时,胶料的M_L较大,t_(10)较短,t_(90)较长,物理性能较差;当稻壳源白炭黑、炭黑用量较为均衡时,硫化胶的物理性能变化不大,动态力学性能较好;稻壳源白炭黑/炭黑用量比对硫化胶耐寒性能的影响不大;当稻壳源白炭黑/炭黑用量比为20/40和25/35时,硫化胶的综合性能较好。     

硫化与补强体系对氯丁橡胶/天然橡胶并用胶性能的影响

研究硫化和补强体系对氯丁橡胶/天然橡胶(并用比为70/30)并用胶性能的影响。结果表明:硫黄对胶料的硬度影响最大,氧化锌/氧化镁/硫黄/促进剂DM用量比为6/3/5/0.3、硫化时间为60 min时,胶料的拉伸强度最高;炭黑N550用量为40份和白炭黑用量为20份时,胶料的加工性能、物理性能、耐水性能和绝缘性能较好。     

炭黑填充氯丁橡胶胶料用新型促进剂和硫化剂

为了研究烷醇酰胺(ALK)用作炭黑填充氯丁橡胶(CR)胶料的新型促进剂和硫化剂的可行性,将ALK的功能与CR传统促进剂和硫化剂亚乙基硫脲(ETU)及氧化镁与氧化锌进行了对比。ALK以1.0、2.0、3.0、4.0份的用量加入炭黑填充CR胶料中。研究发现,在替代ETU时,随ALK用量增大,炭黑填充的含氧化镁和氧化锌CR胶料的焦烧时间和硫化时间缩短。ALK用量在3份以下时,硫化胶的转矩差值增大,拉伸强度和硬度上升。用量超过3份后这些性能下降。还发现,ALK可以硫化炭黑填充CR胶料。不含ETU、氧化镁和氧化锌而含3份ALK的CR胶料的拉伸强度高于由ETU、氧化镁及氧化镁硫化的对比胶料。因此,ALK可以用作炭黑填充氯丁橡胶的促进剂和硫化剂。     

环保型增塑剂腰果壳油对丁腈橡胶性能的影响

研究了腰果壳油(CNSL)用量对丁腈橡胶胶料的硫化特性和硫化胶性能的影响,并与使用邻苯二甲酸二辛酯和环氧大豆油作为增塑剂进行了对比。结果表明,在0～30份(质量)用量内,加入CNSL后胶料的焦烧时间和正硫化时间有所缩短。与加入相同用量的邻苯二甲酸二辛酯和环氧大豆油的胶料及硫化胶相比,使用CNSL的胶料在硫化曲线上的最小转矩和最大转矩以及硫化胶的硬度、定伸应力和耐ASTM1#标准油体积增加率较小;硫化胶的拉伸强度、撕裂强度、扯断伸长率和耐ASTM3#标准油体积增加率较大;硫化胶的耐热空气老化性能较好。     

Utilization of bowstring hemp fiber as a filler in natural rubber compounds

The cure characteristics and physicomechanical properties of natural rubber (standard Nigerian rubber) vulcanizates filled with the fiber of bowstring hemp (Sansevieria liberica) and carbon black were investigated. The results showed that the scorch and cure times decreased, whereas the maximum torques increased, with increasing filler loadings for both bowstring hemp fiber and carbon black filled vulcanizates. The tensile strength of both bowstring hemp fiber and carbon black filled vulcanizates increased to a maximum at a 40 phr filler concentration before decreasing. The elongation at break and rebound resilience decreased, whereas the modulus, specific gravity, abrasion resistance, and hardness increased, with increasing filler contents. The carbon black/natural rubber vulcanizates had higher tensile strength, which was about 1.5 times that of bowstring hemp fiber/natural rubber vulcanizates. This superiority in the tensile strength was probably due to the higher moisture content and larger particle size of the bowstring hemp fiber. However, the bowstring hemp fiber/natural rubber vulcanizates showed superior hardness. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

甲基丙烯酸固态原位接枝改性炭黑对天然橡胶和顺丁橡胶性能的影响

考察了固态原位接枝改性制备的甲基丙烯酸接枝改性炭黑对天然橡胶(NR)和顺丁橡胶。(BR)静态力学性能、动态力学性能的影响。结果表明。甲基丙烯酸改性炭黑比普通商品炭黑填充的NR硫化胶具有更好的静态力学性能;甲基丙烯酸改性炭黑曼有利于降低NR和BR硫化胶的滚动阻力。同时,有利于提高NR硫化胶的抗湿滑性。     

An investigation on the reinforcing potential of red earth as filler for natural rubber compounds

Locally sourced red earth (RE) was air‐dried, pulverized, and screened with a sieve of mesh size 75 nm. It was characterized in terms of its moisture content, loss on ignition, silica content, iodine adsorption number, oil absorption, pH, and metal oxide compositions. Natural rubber, standard Nigerian rubber used for this work was first characterized in terms of its dirt, ash and nitrogen contents, volatile matter, plasticity retention index, and Mooney viscosity. The RE was applied as filler wholly and in blends with standard carbon black, CB (N330) filler in the natural rubber compounding using efficient vulcanization system. The cure and the physicomechanical properties of the compounds and vulcanizates were, respectively, measured as function of filler loading. The results were compared with those of the standard carbon black (N330)‐filled natural rubber. It was found, that the RE‐filled natural rubber showed substantial reinforcement of the rubber, though inferior to carbon black (N330) filled vulcanizates, the tensile strength of the carbon black‐filled vulcanizates is about one half times that of the RE‐filled vulcanizates. The tensile properties of the RE‐filled vulcanizates improved markedly by blending the RE‐filler with the carbon black (N330). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Mechanical properties of deproteinized natural rubber in comparison with synthetic cis‐1, 4 polyisoprene vulcanizates: Gum and black‐filled vulcanizates

Gum and black‐filled vulcanizates having various crosslink densities were prepared from 2 types of rubber, namely, deproteinized natural rubber (DPNR) and synthetic cis‐1, 4 polyisoprene vulcanizates (IR). Their mechanical properties, such as tensile strength, tear strength, abrasion loss, and heat buildup resistance, at various crosslink densities as well as at similar optimum crosslink density were compared. For both gum and black‐filled systems, IR possessed a higher crosslink density than that of DPNR at a fixed curative content. Tensile and tear strength of all vulcanizates passed through a maximum with increasing crosslink density. For gum vulcanizates, tensile and tear strengths of DPNR and IR below the maximum were not much different. However, IR had a narrower tear strength peak relative to DPNR. At a comparable optimum crosslink density, DPNR exhibited higher tensile strength and crack growth resistance than IR. For black‐filled vulcanizates, tensile and tear strengths, and heat buildup resistance of DPNR and IR at a given crosslink density were similar. The results revealed that the properties of gum samples were more dependent upon crosslink density than the black‐filled ones because the reinforcement by carbon black overshadowed the intrinsic properties of the rubbers. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1139–1144, 2005     

Thermal Aging Properties and Molecular Transport of Solvents through Vulcanizates Prepared from Thioglycollic Acid Modified Epoxidized Low Molecular Weight Natural Rubber Blends Filled with Admixtures of Carbon Black and Carbonized Rubber Seed Shell

Physico-mechanical, aging, swelling, solubility, and permeability properties of blends of natural rubber and thioglycollic acid modified epoxidized low molecular weight natural rubber (TGA-ELMWNR) filled with admixtures of carbon black and carbonized rubber seed shell (CRSS) in ketones, alcohols, aldehydes, and petroleum fuels (petrol, kerosene, and diesel) were investigated as a function of different filler composition. The physico-mechanical properties were found reducing as the level of CRSS increases, but were within the accepted level for natural rubber compounds, showing that CRSS can find uses as fillers in materials of low tensile strength. The aging results of all the mixes were nearly of the same magnitude. The swelling and solubility results showed that ketones swell the vulcanizates more and faster than alcohols and than aldehydes. The sorption, diffusion, and permeability of the blends as determined by the gravimetric method confirm the better resistance of blends with higher ratio of carbon black. Petrol was found diffusing through the vulcanizates faster than kerosene and faster than diesel. Above all, replacement of carbon black with 15% carbonized rubber seed shell has not shown any serious deleterious effects on the vulcanizates.     

Guayule natural rubber composites: impact of fillers on their cure characteristics,dynamic and mechanical behavior

Guayule natural rubber (GNR) is an alternative resource of Hevea natural rubber (HNR) with 99.9% cis content in its 1,4-polyisoprene chemical backbone. In this study, compounds were formulated independently with four different reinforcing fillers such as carbon black (HAF), precipitated silica (VN3), fume silica (FUM) and nanofly ash (NFA) for the advancement of GNR based products. The cure characteristic, dynamic-mechanical performance and mechanical properties of GNR composite were studied with the reinforcing effect of different fillers on GNR. The cure characteristic results demonstrated that HAF and FUM silica filled compounds had more processing safety than VN3 and NFA filled compounds. Viscoelastic parameters of the vulcanizates were studied by dynamic mechanical analysis to estimate the glass transition characteristics and dynamic behavior. The higher storage modulus of FUM silica vulcanizate was an indication of superior filler reinforcing nature and improved rolling resistance than other filled systems. Additionally, HRTEM analysis also proved the better filler dispersion ability of FUM silica in GNR matrix. The mechanical properties were studied with a variation of each filler loading of 8, 16, and 32 phr in GNR vulcanizates. The tensile strength of each filled system increased with an increase of filler content from 8 to 32 phr. In comparison, FUM silica GNR vulcanizates exhibited better mechanical properties, therefore, it was considered as a better structure-performance composite than those of HAF, VN3 and NFA filled composites.

     

液体聚异戊二烯对天然橡胶/聚丁二烯橡胶硫化胶微观结构和性能的影响

研究了液体聚异戊二烯(LIR)作为增塑剂对天然橡胶(NR)/聚丁二烯橡胶(BR)硫化胶微观结构、弯曲疲劳性能、压缩疲劳性能和动态力学性能的影响,并与加入工业用增塑剂芳烃油的硫化胶进行了对比。结果表明,加入LIR较芳烃油有利于炭黑在NR/BR体系中的分散;随着LIR用量的增加,NR/BR硫化胶的耐屈挠疲劳性能基本不变;与芳烃油增塑的NR/BR体系相比,LIR增塑NR/BR体系的耐屈挠疲劳性能较优,压缩疲劳生热和压缩永久变形较低;加入LIR降低了硫化胶滚动阻力的同时减弱了其抗湿滑性。     

THERMAL AGING PROPERTIES AND MOLECULAR TRANSPORT OF SOLVENTS THROUGH VULCANIZATES PREPARED FROM THIOGLYCOLLIC ACID MODIFIED EPOXIDIZED LOW MOLECULAR WEIGHT NATURAL RUBBER BLENDS FILLED WITH ADMIXTURES OF CARBON BLACK AND CARBONIZED RUBBER SEED SHELL

Physico-mechanical, aging, swelling, solubility, and permeability properties of blends of natural rubber (NR) and thioglycollic acid modified epoxidized low molecular weight natural rubber (TGA-ELMWNR) filled with admixtures of carbon black (CB) and carbonized rubber seed shell (CRSS) in ketones, alcohols, aldehydes, and petroleum fuels (petrol, kerosene, and diesel) were investigated as a function of different filler compositions. The physico-mechanical properties were found decreasing as the level of CRSS increases, but were within the accepted level for natural rubber compounds, showing that CRSS can find uses as fillers in materials of low tensile strength. The aging results of all the mixes were nearly of the same magnitude. The swelling and solubility results showed that ketones swell the vulcanizates more and faster than alcohols and aldehydes. The sorption, diffusion, and permeability of the blends as determined from the gravimetric method confirm the better resistance of blends with higher ratio of carbon black. Petrol was found diffusing through the vulcanizates faster than kerosene and faster than diesel. Above all, replacement of carbon black with 15% carbonized rubber seed shell has not shown any serious deleterious effects on the vulcanizates.     

Use of rice husk ash as filler in natural rubber vulcanizates: In comparison with other commercial fillers

Rice husk ash is mainly composed of silica and carbon black remaining from incomplete combustion. Both silica and carbon black have long been recognized as the main reinforcing fillers used in the rubber industry to enhance certain properties of rubber vulcanizates, such as modulus and tensile strength. In this study, two grades of rice husk ash (low‐ and high‐carbon contents) were used as filler in natural rubber. Comparison was made of the reinforcing effect between rice husk ashes and other commercial fillers such as talcum, china clay, calcium carbonate, silica, and carbon black. Fourier transform infrared spectroscopy (FTIR) analysis was employed to study the presence of functional groups on the ash surface. The effect of silane coupling agent, bis(3‐triethoxysilylpropyl)tetrasulfane (Si‐69), on the properties of ash‐filled vulcanizates was also investigated. It was found that both grades of rice husk ash provide inferior mechanical properties (tensile strength, modulus, hardness, abrasion resistance, and tear strength) in comparison with reinforcing fillers such as silica and carbon black. However, the mechanical properties of the vulcanizates filled with rice husk ash are comparable to those filled with inert fillers. The addition of silane‐coupling agent has little effect on the properties of the ash‐filled vulcanizates. This is simply due to the lack of silanol groups on the ash surface. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2485–2493, 2002     

THERMAL AGING PROPERTIES AND MOLECULAR TRANSPORT OF SOLVENTS THROUGH VULCANIZATES PREPARED FROM THIOGLYCOLLIC ACID MODIFIED EPOXIDIZED LOW MOLECULAR WEIGHT NATURAL RUBBER BLENDS FILLED WITH ADMIXTURES OF CARBON BLACK AND CARBONIZED RUBBER SEED SHELL

Physico-mechanical, aging, swelling, solubility, and permeability properties of blends of natural rubber (NR) and thioglycollic acid modified epoxidized low molecular weight natural rubber (TGA-ELMWNR) filled with admixtures of carbon black (CB) and carbonized rubber seed shell (CRSS) in ketones, alcohols, aldehydes, and petroleum fuels (petrol, kerosene, and diesel) were investigated as a function of different filler compositions. The physico-mechanical properties were found decreasing as the level of CRSS increases, but were within the accepted level for natural rubber compounds, showing that CRSS can find uses as fillers in materials of low tensile strength. The aging results of all the mixes were nearly of the same magnitude. The swelling and solubility results showed that ketones swell the vulcanizates more and faster than alcohols and aldehydes. The sorption, diffusion, and permeability of the blends as determined from the gravimetric method confirm the better resistance of blends with higher ratio of carbon black. Petrol was found diffusing through the vulcanizates faster than kerosene and faster than diesel. Above all, replacement of carbon black with 15% carbonized rubber seed shell has not shown any serious deleterious effects on the vulcanizates.